Securities - Schedule of Available For Sale Securities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale
Amortized Cost	$ 17,808	$ 16,680
Gross Unrealized Gains	126	41
Gross Unrealized Losses	145	407
Fair Value	17,789	16,314
US Treasury and Government [Member]
Securities available for sale
Amortized Cost	5,485	3,572
Gross Unrealized Gains	6	1
Gross Unrealized Losses	53	144
Fair Value	5,438	3,429
U.S. government agency and government-sponsored agencies
Securities available for sale
Amortized Cost	5,491	8,168
Gross Unrealized Gains	13	7
Gross Unrealized Losses	36	168
Fair Value	5,468	8,007
Privately issued
Securities available for sale
Amortized Cost	759	887
Gross Unrealized Gains	5	0
Gross Unrealized Losses	2	23
Fair Value	762	864
Privately issued - commercial mortgage-backed securities
Securities available for sale
Amortized Cost	3,461	1,198
Gross Unrealized Gains	56	3
Gross Unrealized Losses	28	21
Fair Value	3,489	1,180
Collateralized loan obligations
Securities available for sale
Amortized Cost	1,499	1,492
Gross Unrealized Gains	0	0
Gross Unrealized Losses	8	18
Fair Value	1,491	1,474
Direct bank purchase bonds
Securities available for sale
Amortized Cost	911	1,190
Gross Unrealized Gains	43	30
Gross Unrealized Losses	18	30
Fair Value	936	1,190
Other
Securities available for sale
Amortized Cost	202	173
Gross Unrealized Gains	3	0
Gross Unrealized Losses	0	3
Fair Value	$ 205	$ 170

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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+ References

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